A lonely and potentially sexually frustrated dolphin has been blamed for a spike in attacks on swimmers in a Japanese seaside town.

The bottlenose dolphin is believed to be behind 18 attacks near the town of Mihama so far this year, with one primary school-aged child’s finger needing at least 20 stitches.

At least six people were injured in attacks last year, leaving one swimmer with broken ribs. Another person was injured in a 2022 attack.

It has led officials to warn that not only can the mammals “bite you with their sharp teeth and cause you to bleed”, but they can also "drag you into the sea, which could be life-threatening”.

Despite their reputation as friendly animals, dolphin attacks can be fatal. In 1994, a dolphin in Brazil attacked two male swimmers who tried to ride it, killing one and injuring the other. The dolphin, nicknamed Tião, was believed to have injured at least 22 people before that.